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1.
Ecol Appl ; 32(4): e2551, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35094452

RESUMEN

Effective conservation requires understanding the processes that determine population outcomes. Too often, we assume that protected areas conserve wild populations despite evidence that they frequently fail to do so. Without large-scale studies, however, we cannot determine what relationships are the product of localized conditions versus general patterns that inform conservation more broadly. Leopards' (Panthera pardus) basic ecology is well studied but little research has investigated anthropogenic effects on leopard density at broad scales. We investigated the drivers of leopard density among 27 diverse protected areas in northeastern South Africa to understand what conditions facilitate abundant populations. We formulated 10 working hypotheses that considered the relative influence of bottom-up biological factors and top-down anthropogenic factors on leopard density. Using camera-trap survey data, we fit a multi-session spatial capture-recapture model with inhomogenous density for each hypothesis and evaluated support using an information theoretic approach. The four supported hypotheses indicated that leopard density is primarily limited by human impacts, but that habitat suitability and management conditions also matter. The proportion of camera stations that recorded domestic animals, a proxy for the extent of human impacts and protected area effectiveness, was the only predictor variable present in all four supported models. Protected areas are the cornerstone of large felid conservation, but only when the human-wildlife interface is well managed and protected areas shelter wildlife populations from anthropogenic impacts. To ensure the long-term abundance of large carnivore populations, reserve managers should recognize the ineffectiveness of "paper parks" and promote contiguous networks of protected areas that offer leopards and other large mammal populations greater space and reduced human impacts.


Asunto(s)
Efectos Antropogénicos , Conservación de los Recursos Naturales , Ecosistema , Panthera/fisiología , Animales , Humanos , Fotograbar , Densidad de Población
2.
Conserv Biol ; 36(2): e13813, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34342042

RESUMEN

Understanding how human modification of the landscape shapes vertebrate community composition is vital to understanding the current status and future trajectory of wildlife. Using a participatory approach, we deployed the largest camera-trap network in Mesoamerica to date to investigate how anthropogenic disturbance shapes the occupancy and co-occurrence of terrestrial vertebrate species in a tropical biodiversity hotspot: the Osa Peninsula, Costa Rica. We estimated species richness in different categories of land protection with rarefaction analysis and estimated the expected occupancy with a joint species distribution model that included covariates for anthropogenic disturbance, land protection, habitat quality, and habitat availability. Areas with the most stringent land-use protections (e.g., Corcovado National Park, 24 species [95% CI 23-25]) harbored significantly more species than unprotected areas (20 species [19.7-20.3]), mainly due to a reduced presence of large-bodied species of conservation concern in unprotected areas (e.g., jaguar Panthera onca and white-lipped peccary Tayassu pecari). Small-bodied generalist species, such as opossums (Didelphidae) and armadillos (Dasypus novemcinctus), in contrast, were more common at disturbed sites, resulting in a significant difference in vertebrate community composition between sites with low and high disturbance. Co-occurrence of species was also mainly associated with response to disturbance. Similar responses to disturbance create two groups of species, those whose site-level occupancy usually increased as anthropogenic disturbance increased and those whose estimated occupancy decreased. The absence of large-bodied species entails an important loss of ecological function in disturbed areas and can hinder forest development and maintenance. Efforts to protect and restore forested landscapes are likely having a positive effect on the abundance of some threatened species. These efforts, however, must be sustained and expanded to increase connectivity and ensure the long-term viability of the wildlife community.


Perturbaciones Humanas y Cambios en la Composición de la Comunidad de Vertebrados en un Punto Caliente de Biodiversidad Resumen El entendimiento de cómo las modificaciones humanas del paisaje conforman la composición de las comunidades de vertebrados es vital para entender el estado actual y la trayectoria futura de la fauna. Mediante una estrategia participativa, desplegamos la mayor red de cámaras trampa en Mesoamérica hasta la fecha para investigar cómo la perturbación antropogénica determina la ocupación y coocurrencia de las especies terrestres de vertebrados en un punto caliente de biodiversidad tropical: la Península de Osa, Costa Rica. Estimamos la riqueza de especies en diferentes categorías de protección de suelo con un análisis de rarefacción y estimamos la ocupación esperada con un modelo de distribución conjunta de especies que incluyó covariables para la perturbación antropogénica, la protección del suelo, la calidad del hábitat y la disponibilidad del hábitat. Las áreas con la protección más estricta de uso de suelo (p. ej.: Parque Nacional Corcovado, 24 especies [95% CI 23-25]) albergaron significativamente a más especies que las áreas desprotegidas (20 especies [19.7-20.3]), principalmente debido a la presencia reducida de especies de talla grande de interés para la conservación en las áreas desprotegidas (p. ej.: el jaguar Panthera onca, el pecarí de labios blancos, Tayassu pecari). Al contrario, las especies generalistas de talla pequeña, como las zarigüeyas (Didelphidae) y el armadillo (Dasypus novemcinctus) fueron más comunes en los sitios perturbados, lo que resulta en una diferencia significativa en la composición de las comunidades de vertebrados entre los sitios con una perturbación baja y alta. La coocurrencia de especies también estuvo asociada principalmente con la respuesta a la perturbación. Las respuestas similares a la perturbación crean dos grupos de especies: aquellas cuya ocupación a nivel de sitio generalmente incrementó conforme incrementó la perturbación antropogénica y aquellas cuya ocupación estimada disminuyó. La ausencia de especies de talla grande conlleva una pérdida importante de la función ecológica en las áreas perturbadas y puede dificultar el desarrollo y mantenimiento del bosque. Los esfuerzos para proteger y restaurar los paisajes forestales probablemente estén teniendo un efecto positivo sobre la abundancia de algunas especies amenazadas. Estos esfuerzos, sin embargo, deben ser sostenidos y expandidos para incrementar la conectividad y asegurar la viabilidad a largo plazo de la comunidad faunística.


Asunto(s)
Conservación de los Recursos Naturales , Panthera , Animales , Animales Salvajes , Biodiversidad , Conservación de los Recursos Naturales/métodos , Ecosistema , Bosques , Humanos , Panthera/fisiología , Vertebrados
3.
Biol Reprod ; 105(1): 137-147, 2021 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-33864060

RESUMEN

In the present study, we investigated the effect of the synthetic analog of prostaglandin F2α (PGF2α)-cloprostenol-on cultured steroidogenic luteal cells of selected felid species over a 2-day culture period. The changes induced by cloprostenol were measured based on progesterone concentration and mRNA expression analysis of selected genes. Cloprostenol significantly reduced concentration of progesterone in cell culture medium of small luteal cells isolated from domestic cat corpora lutea (CL) at the development/maintenance stage (P < 0.05), but did not influence progesterone production in cultured cells from the regression stage. A decrease or complete silencing of progesterone production was also measured in cultured luteal cells of African lion (formation stage) and Javan leopard (development/maintenance stage). Gene-expression analysis by real-time PCR revealed that treatment with cloprostenol did not have an influence on expression of selected genes coding for enzymes of steroidogenesis (StAR, HSD3B, CYP11A1) or prostaglandin synthesis (PTGS2, PGES), nor did it effect hormone receptors (AR, ESR1, PGR, PTGER2), an anti-oxidative enzyme (SOD1) or factors of cell apoptosis (FAS, CASP3, TNFRSF1B, BCL2) over the studied period. Significant changes were measured only for expressions of luteinizing hormone (P < 0.05), prolactin (P < 0.05) and PGF2α receptors (P < 0.005) (LHCGR, PRLR, and PTGFR). The obtained results confirm that PGF2α/cloprostenol is a luteolytic agent in CL of felids and its impact on progesterone production depends on the developmental stage of the CL. Cloprostenol short-term treatment on luteal cells was associated only with functional but not structural changes related to luteal regression.


Asunto(s)
Gatos/fisiología , Cloprostenol/farmacología , Leones/fisiología , Células Lúteas/efectos de los fármacos , Luteólisis/psicología , Luteolíticos/farmacología , Panthera/fisiología , Animales , Células Cultivadas , Femenino
4.
Zoo Biol ; 40(4): 280-287, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33739467

RESUMEN

Biological resource banks represent valuable tools for the conservation of species vulnerable to extinction, such as the jaguar. Cryobanks of skins have the potential to safeguard rare genotypes, allowing the potential exploitation of biological samples in animal multiplication technologies and the study of genetic variability. Determination of the most suitable skin regions for tissue conservation can help increase the efficiency of cryobanks and the storage of biological samples. To this end, we evaluated the effects of vitrification of skin tissues from the ear, caudal, and femoral regions of a post-mortem jaguar belonging to a zoo in Brazil. Non-vitrified and vitrified samples were evaluated and compared using quantitative methods, focusing on skin thickness, cell quantification, number of perinuclear halos, collagen and elastic density, and proliferative activity. No differences were observed in skin thickness, number of perinuclear halos, elastic density, and proliferative activity between non-vitrified and vitrified tissues in skin from any region. However, vitrified tissues derived from femoral skin showed a reduction in the number of fibroblasts, epidermal cells and collagen density compared to non-vitrified tissues. In summary, the ear and caudal regions provided the best conservation of somatic tissues derived from jaguars, and skin samples from these regions are therefore the most suitable for the formation of cryobanks.


Asunto(s)
Criopreservación/veterinaria , Panthera/fisiología , Fenómenos Fisiológicos de la Piel , Piel/anatomía & histología , Manejo de Especímenes , Vitrificación , Animales , Oído , Cola (estructura animal)
5.
Zoo Biol ; 38(3): 292-304, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30955226

RESUMEN

This experiment was conducted to study the effect of gradual replacement of dietary buffalo meat on the bone (BMB) with chicken carcass (CC) on nutrient utilization, serum cortisol, and total serum antioxidant profile of zoo-housed Indian leopard. Twelve adult leopards were randomly distributed into a replicated Latin square design comprising three treatments, three periods, four animals, and three sequences. Leopards in group T1 were fed normal zoo diet of BMB. On the basis of dry matter, 10% and 20% of BMB was replaced with CC in groups T2 and T3 , respectively. Each experimental period comprised 21 days. During each period, a digestion trial of 4-day collection period was conducted after an adaptation period of 17 days. On Day 21 of each experimental period, blood was collected from all the animals by puncturing the ventral coccygial vein. Intake and apparent digestibility of major nutrients were similar among the groups. Replacement of 20% BMB with addition of CC increased (p < 0.001) the calculated supply of I, niacin, and vitamin A. Carotenoid intake increased (p < 0.01) with increased level of CC in the diet. Serum concentration of cortisol decreased (p < 0.01) whereas serum concentration of total carotenoids increased (p < 0.001) with increased level of CC in the diet. Serum concentration of antioxidant enzymes increased (p < 0.001) with increased level of CC in the diet. It was concluded that replacement of 20% of BMB with CC increased antioxidant profile. This may reduce oxidative stress in zoo-housed Indian leopards without any adverse effect on nutrient utilization.


Asunto(s)
Antioxidantes/análisis , Dieta/veterinaria , Panthera/sangre , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Animales de Zoológico/sangre , Búfalos , Carotenoides/sangre , Pollos , Hidrocortisona/sangre , India , Panthera/fisiología , Distribución Aleatoria
6.
Zoo Biol ; 38(2): 214-219, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30653720

RESUMEN

Housing bachelor groups is a necessary aspect of the care and husbandry of non-breeding individuals in zoological collections. Intraspecific aggressive behaviors may occur in this setting despite management strategies designed to mitigate these behaviors. Androgens (including testosterone) are associated with aggression in male species and interventional techniques to alter the animals' physiology to modify aggressive behavior are sometimes required. When agonistic behavior and physical aggression in two mature male Amur leopards housed together at Tayto Park escalated, despite all strategic management involvements, further intervention to moderate aggression was required. The gonadotropin-releasing hormone (GnRH) agonist, deslorelin, has been found to be effective in reducing androgens in domestic and non-domestic carnivores. We hypothesized that deslorelin's suppressive effect on hypothalamic-pituitary-gonadal axis would mitigate intraspecific aggression in two male intact leopards. Behavioral observations were carried out pre- and post-implant implantation of 9.4 mg deslorelin implant. The frequency of agonistic/aggressive behaviors for both leopards declined significantly (p < 0.05), as did marking behaviors post-implantation (p < 0.001). The insertion of deslorelin implants in two male intact leopards demonstrating increased frequency and severity of aggressive behaviors resulted in a reduction of the frequency of these behaviors. Deslorelin implantation should be considered for management of interspecific aggression of intact male leopards in bachelor groups.


Asunto(s)
Agresión/efectos de los fármacos , Animales de Zoológico , Hormona Liberadora de Gonadotropina/agonistas , Panthera/fisiología , Pamoato de Triptorelina/análogos & derivados , Animales , Implantes de Medicamentos , Inhibidores Enzimáticos/administración & dosificación , Inhibidores Enzimáticos/farmacología , Masculino , Pamoato de Triptorelina/administración & dosificación , Pamoato de Triptorelina/farmacología
7.
Proc Biol Sci ; 285(1877)2018 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-29695443

RESUMEN

Although leopards are the most widespread of all the big cats and are known for their adaptability, they are elusive and little is known in detail about their movement and hunting energetics. We used high-resolution GPS/IMU (inertial measurement unit) collars to record position, activity and the first high-speed movement data on four male leopards in the Okavango Delta, an area with high habitat diversity and habitat fragmentation. Leopards in this study were generally active and conducted more runs during the night, with peaks in activity and number of runs in the morning and evening twilight. Runs were generally short (less than 100 m) and relatively slow (maximum speed 5.3 m s-1, mean of individual medians) compared to other large predators. Average daily travel distance was 11 km and maximum daily travel distance was 29 km. No direct correlation was found between average daily temperature and travel distance or between season and travel distance. Total daily energy requirements based on locomotor cost and basal metabolic rate varied little between individuals and over time. This study provides novel insights into movement patterns and athletic performance of leopards through quantitative high-resolution measurement of the locomotor, energetic, spatial and temporal movement characteristics. The results are unbiased by methodological and observational limitations characteristic of previous studies and demonstrate the utility of applying new technologies to field studies of elusive nocturnal species.


Asunto(s)
Metabolismo Energético , Movimiento , Panthera/fisiología , Territorialidad , Animales , Botswana , Sistemas de Información Geográfica , Masculino , Condicionamiento Físico Animal , Carrera , Análisis Espacial
8.
Am J Primatol ; 80(12): e22932, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30537388

RESUMEN

Predation is widely recognized as an important selective pressure on prey animals such as baboons (Papio spp.), which face high leopard (Panthera pardus) predation risk, particularly at night. Baboons regularly sleep on cliff faces and in trees at night, ostensibly to avoid such predators. Despite retreating to such "refuges," baboons are most often killed by leopards at or near their sleeping sites. Because of the challenges of studying nocturnal behavior and human-averse predators, few systematic data exist to reveal how leopard ranging near baboon sleeping sites influences baboons' selection of sites and behavior at those sites. To investigate leopard-baboon dynamics at sleeping sites we deployed GPS/VHF radio collars on six representatives of four baboon groups and four leopards during a 14-month field study in Kenya. We used locations recorded every 15 min to identify baboons' cliffside and riverine sleeping sites, the frequency and duration of leopard visits to these sites, and baboons' adjustments in site use after leopard visits. Collared leopards visited riverine sites more frequently than cliffside sites, whereas most baboon groups strongly preferred cliffside sites, suggesting that leopard visits were often due to factors other than baboon presence, and that baboons used cliffside sites to reduce their risk of leopard predation. Regardless of type, collared leopards remained near baboon-occupied sleeping sites longer than vacant ones, indicating interest in hunting baboons then. Baboons at riverine sites departed later on mornings after leopard visits. Baboon groups occasionally shared sleeping sites simultaneously, possibly reducing risk through dilution. However, they did not reduce risk by frequently changing sleeping sites, minimizing detection at sleeping sites, or after leopard visits, arriving earlier the next evening or moving to a different site. Future research should explore if baboons readily detect nocturnal leopard presence and if predation-related changes in sleeping site use have cascading ecological effects.


Asunto(s)
Panthera/fisiología , Papio anubis/fisiología , Conducta Predatoria , Sueño , Animales , Femenino , Masculino
9.
J Anim Ecol ; 86(3): 634-644, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28217865

RESUMEN

Food caching is a common strategy used by a diversity of animals, including carnivores, to store and/or secure food. Despite its prevalence, the drivers of caching behaviour, and its impacts on individuals, remain poorly understood, particularly for short-term food cachers. Leopards Panthera pardus exhibit a unique form of short-term food caching, regularly hoisting, storing and consuming prey in trees. We explored the factors motivating such behaviour among leopards in the Sabi Sand Game Reserve, South Africa, associated with four not mutually exclusive hypotheses: food-perishability, consumption-time, resource-pulse and kleptoparasitism-avoidance. Using data from 2032 prey items killed by 104 leopards from 2013 to 2015, we built generalized linear mixed models to examine how hoisting behaviour, feeding time and the likelihood of a kill being kleptoparasitized varied with leopard sex and age, prey size and vulnerability, vegetation, elevation, climate, and the immediate and long-term risk posed by dominant competitors. Leopards hoisted 51% of kills. They were more likely to hoist kills of an intermediate size, outside of a resource pulse and in response to the presence of some competitors. Hoisted kills were also fed on for longer than non-hoisted kills. At least 21% of kills were kleptoparasitized, mainly by spotted hyaenas Crocuta crocuta. Kills were more likely to be kleptoparasitized at lower temperatures and if prey were larger, not hoisted, and in areas where the risk of encountering hyaenas was greatest. Female leopards that suffered higher rates of kleptoparasitism exhibited lower annual reproductive success than females that lost fewer kills. Our results strongly support the kleptoparasitism-avoidance hypothesis and suggest hoisting is a key adaptation that enables leopards to coexist sympatrically with high densities of competitors. We further argue that leopards may select smaller-sized prey than predicted by optimal foraging theory, to balance trade-offs between kleptoparasitic losses and the energetic gains derived from killing larger prey. Although caching may provide the added benefits of delaying food perishability and enabling consumption over an extended period, the behaviour primarily appears to be a strategy for leopards, and possibly other short-term cachers, to reduce the risks of kleptoparasitism.


Asunto(s)
Cadena Alimentaria , Hyaenidae/fisiología , Panthera/fisiología , Conducta Predatoria , Animales , Femenino , Masculino , Sudáfrica
10.
J Exp Biol ; 219(Pt 23): 3738-3749, 2016 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-27634400

RESUMEN

Mandibular force profiles apply the principles of beam theory to identify mandibular biomechanical properties that reflect the bite force and feeding strategies of extant and extinct predators. While this method uses the external dimensions of the mandibular corpus to determine its biomechanical properties, more accurate results could potentially be obtained by quantifying its internal cortical bone distribution. To test this possibility, mandibular force profiles were calculated using both external mandibular dimensions ('solid mandible model') and quantification of internal bone distribution of the mandibular corpus obtained from computed tomography scans ('hollow mandible model') for five carnivorans (Canis lupus, Crocuta crocuta, Panthera leo, Neofelis nebulosa and the extinct Canis dirus). Comparison reveals that the solid model slightly overestimates mandibular biomechanical properties, but the pattern of change in biomechanical properties along the mandible remains the same. As such, feeding behavior reconstructions are consistent between the two models and are not improved by computed tomography. Bite force estimates produced by the two models are similar, except in C. crocuta, where the solid model underestimates bite force by 10-14%. This discrepancy is due to the more solid nature of the C. crocuta mandible relative to other carnivorans. Therefore, computed tomography improves bite force estimation accuracy for taxa with thicker mandibular corpora, but not significantly so otherwise. Bite force estimates derived from mandibular force profiles are far closer to empirically measured bite force than those inferred from jaw musculature dimension. Consequently, bite force estimates derived from this method can be used to calibrate finite-element analysis models.


Asunto(s)
Fenómenos Biomecánicos/fisiología , Fuerza de la Mordida , Carnívoros/fisiología , Conducta Alimentaria/fisiología , Hyaenidae/fisiología , Mandíbula/fisiología , Panthera/fisiología , Lobos/fisiología , Animales , Análisis de Elementos Finitos , Modelos Biológicos , Conducta Predatoria , Estrés Mecánico
11.
Gen Comp Endocrinol ; 225: 95-103, 2016 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-26399935

RESUMEN

Basic reproductive information in female jaguars (Panthera onca) is lacking, thus longitudinal fecal samples from seven females were analyzed via enzyme immunoassay to measure estradiol and progestin metabolites throughout the year. Mean estrus length of 194 estrus periods measured hormonally was 6.5±0.3d, mean peak fecal estradiol concentration was 138.7±5.7ng/g; and in one female, estrus resumption occurred approximately 15d post-partum. Ovulation, as indicted by sustained elevated progestin concentrations (>20d), was successfully induced one time by treatment with exogenous hormones in one female and by physical vaginal stimulation in two females a combined total of three times. Elevated fecal progestin was observed outside exogenous stimulation on five occasions, suggesting ovulation occurred spontaneously. Mean length of physically induced and spontaneous pseudopregnancies was 24.7±4.2d and 29.6±2.6d, respectively, and mean length of pregnancy (n=2) was 98.0±0.0d. Mean peak progestin concentration for spontaneous and induced pseudopregnancies, and pregnancy was 7.4±1.4µg/g, 6.4±1.2µg/g, and 13.7±1.0µg/g, respectively. This data suggests jaguars are polyestrous and generally induced ovulators, with a moderate incidence of spontaneous ovulation. Additionally, two protocols to successfully stimulate ovarian activity in jaguars are described.


Asunto(s)
Estradiol/análisis , Ciclo Estral/fisiología , Estro/fisiología , Panthera/fisiología , Progestinas/análisis , Reproducción/fisiología , Animales , Estradiol/metabolismo , Heces/química , Femenino , Ovulación/fisiología , Periodo Posparto , Embarazo
12.
Rev Biol Trop ; 64(4): 1451-68, 2016 Dec.
Artículo en Español | MEDLINE | ID: mdl-29465909

RESUMEN

Information on the ecology of jaguars (Panthera onca) in "El Cielo" Biosphere Reserve in Tamaulipas, Mexico is scant and limited to anecdotic records in a handful of publications. The objectives of our study were to: a) determine population density and structure of jaguars, b) compare their activity patterns with that of pumas (Puma concolor), c) ascertain potential prey relative abundance, and d) evaluate local resident's perception on loss of domestic animals due to jaguar predation. Between April 2013 and April 2014 we conducted camera trapping in Gomez Farias Township with a total sampling effort of 8 580 camera trap days. Besides, we completed 136 semi-structured interviews among local residents of Gomez Farias and Llera Townships to gather information on domestic animal losses attributed to jaguars and other carnivores. We identified eight different jaguar individuals during a complete year of camera-trapping, composed of four adult females, one juvenile female, two adult males and one juvenile male. We estimated a jaguar density of 5.9 ± 1.3 jaguars/100 km². Activity patterns for jaguars and pumas were similar as both were nocturnal and crepuscular in nature. The most abundant potential prey species for jaguars in the study site were Crax rubra, Cuniculus paca, Mazama temama, Odocoileus virginianus and Didelphis virginiana; while the rarest were Mephitis macroura and Procyon lotor. Interview results suggested that chickens, dogs, and house cats were the most consumed domestic animals from all reported losses by local residents (n= 107). This study represents the first attempt to describe jaguar ecology in "El Cielo" Biosphere Reserve; however, there is a need of additional monitoring efforts to determine the current status of jaguars in a larger area in order to establish conservation strategies. Finally, this jaguar population may have an important role in maintaining the species in the Sierra Madre Oriental biological corridor connecting populations in Nuevo Leon and San Luis states in Northeastern Mexico.


Asunto(s)
Ecosistema , Panthera/fisiología , Distribución Animal , Animales , Femenino , Masculino , México , Densidad de Población , Conducta Predatoria , Puma/fisiología
13.
J Exp Biol ; 218(Pt 15): 2402-9, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26246610

RESUMEN

Genetically based modifications of hemoglobin (Hb) function that increase blood-O2 affinity are hallmarks of hypoxia adaptation in vertebrates. Among mammals, felid Hbs are unusual in that they have low intrinsic O2 affinities and reduced sensitivities to the allosteric cofactor 2,3-diphosphoglycerate (DPG). This combination of features compromises the acclimatization capacity of blood-O2 affinity and has led to the hypothesis that felids have a restricted physiological niche breadth relative to other mammals. In seeming defiance of this conjecture, the snow leopard (Panthera uncia) has an extraordinarily broad elevational distribution and occurs at elevations above 6000 m in the Himalayas. Here, we characterized structural and functional variation of big cat Hbs and investigated molecular mechanisms of Hb adaptation and allosteric regulation that may contribute to the extreme hypoxia tolerance of the snow leopard. Experiments revealed that purified Hbs from snow leopard and African lion exhibited equally low O2 affinities and DPG sensitivities. Both properties are primarily attributable to a single amino acid substitution, ß2His→Phe, which occurred in the common ancestor of Felidae. Given the low O2 affinity and reduced regulatory capacity of feline Hbs, the extreme hypoxia tolerance of snow leopards must be attributable to compensatory modifications of other steps in the O2-transport pathway.


Asunto(s)
Adaptación Biológica/fisiología , Altitud , Hemoglobinas/metabolismo , Oxígeno/metabolismo , Panthera/fisiología , 2,3-Difosfoglicerato/metabolismo , Regulación Alostérica/fisiología , Secuencia de Aminoácidos , Animales , Hemoglobinas/genética , Datos de Secuencia Molecular , Panthera/genética , Análisis de Secuencia de ADN
14.
Ecol Appl ; 25(7): 1911-21, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26591456

RESUMEN

Natal dispersal promotes inter-population linkage, and is key to spatial distribution of populations. Degradation of suitable landscape structures beyond the specific threshold of an individual's ability to disperse can therefore lead to disruption of functional landscape connectivity and impact metapopulation function. Because it ignores behavioral responses of individuals, structural connectivity is easier to assess than functional connectivity and is often used as a surrogate for landscape connectivity modeling. However using structural resource selection models as surrogate for modeling functional connectivity through dispersal could be erroneous. We tested how well a second-order resource selection function (RSF) models (structural connectivity), based on GPS telemetry data from resident adult leopard (Panthera pardus L.), could predict subadult habitat use during dispersal (functional connectivity). We created eight non-exclusive subsets of the subadult data based on differing definitions of dispersal to assess the predictive ability of our adult-based RSF model extrapolated over a broader landscape. Dispersing leopards used habitats in accordance with adult selection patterns, regardless of the definition of dispersal considered. We demonstrate that, for a wide-ranging apex carnivore, functional connectivity through natal dispersal corresponds to structural connectivity as modeled by a second-order RSF. Mapping of the adult-based habitat classes provides direct visualization of the potential linkages between populations, without the need to model paths between a priori starting and destination points. The use of such landscape scale RSFs may provide insight into predicting suitable dispersal habitat peninsulas in human-dominated landscapes where mitigation of human-wildlife conflict should be focused. We recommend the use of second-order RSFs for landscape conservation planning and propose a similar approach to the conservation of other wide-ranging large carnivore species where landscape-scale resource selection data already exist.


Asunto(s)
Distribución Animal , Ecosistema , Panthera/fisiología , Envejecimiento , Animales , Conservación de los Recursos Naturales , Femenino , Masculino , Modelos Biológicos , Reproducibilidad de los Resultados , Sudáfrica
15.
Zoo Biol ; 34(2): 189-92, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25652718

RESUMEN

To fulfill an educational or visitor-related role in the zoo's collection, a species needs to be visible to the visiting public. However, this may not always be achievable for animals housed in naturalistic enclosures, particularly species which are highly camouflaged and have an elusive nature, such as jaguars. Four jaguars housed at Chester Zoo (UK) were studied to assess the quality of visibility from the public viewing area and to provide recommendations for assessing visibility to evaluate the educational role of elusive species. Data were recorded on whether the jaguar could be seen, the proportion of the body that was visible and their behavior. The jaguars could be seen 19.5% (i.e. quantity), from the public viewing area, of the observed time. 69.2% of this time the whole of the jaguars' body was on-show and it was possible to observe their behavior during all of these observations. However, when less of the body was visible, the behavior of the jaguars could be observed on significantly fewer occasions (P < .001). When we incorporate behavior and proportion of body into the analysis and look at 'educationally meaningful visibility' (i.e. whole of the animal's body and a behavior could be observed), then the measurement of visibility is reduced to 13.3% (i.e. quality). A simple yes or no, in relation to whether an animal is visible or not, does not give us the detail needed to assess if a species is fulfilling an educational role. Potential solutions to address poor visibility are also discussed.


Asunto(s)
Bienestar del Animal/normas , Animales de Zoológico/fisiología , Panthera/fisiología , Animales , Animales de Zoológico/psicología , Conducta Animal , Conservación de los Recursos Naturales , Femenino , Vivienda para Animales/normas , Modelos Lineales , Masculino , Panthera/psicología , Densidad de Población , Relaciones Públicas
16.
Zoo Biol ; 34(2): 153-62, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25652645

RESUMEN

An experiment was conducted to determine the effect of incorporating Jerusalem artichoke (JA) as a prebiotic in the diet of Indian leopards (n = 11 adults) fed a meat-on-bone diet. The trial consisted of three periods (A1 , B, and A2 ). Each period comprised 17 days of adaptation and four days of collection. During the control periods (A1 and A2 ), the leopards were fed their normal zoo diets of 2.5-3 kg of buffalo meat-on-bone six days a week without any supplement. During trial B, meat-on-bone diets of the leopards were supplemented with JA at 2% of dietary dry matter (DM). Meat consumption was similar among the treatments. Supplementation of JA decreased the digestibility of crude protein (P < 0.01). Digestibilities of organic matter and ether extract were similar among the treatments. Serum concentrations of urea and triglycerides were lower (P < 0.05) when JA was added to the diet. Incorporation of JA to the basal diet increased fecal concentrations of acetate (P < 0.01), butyrate (P < 0.01), lactate (P < 0.01), Lactobacillus spp., and Bifidobacterium spp. (P < 0.01) with a simultaneous decrease in the concentration of ammonia (P < 0.01), Clostridia spp. (P < 0.01), and fecal pH (P < 0.01). Fecal microbial profiles and hind gut fermentation were improved, without any adverse effects on feed consumption, nutrient utilization, and serum metabolite profiles. Results of this experiment showed that feeding JA at 2% DM in the whole diet could be potentially beneficial for captive Indian leopards fed meat-on-bone diets.


Asunto(s)
Fenómenos Fisiológicos Nutricionales de los Animales , Dieta/veterinaria , Helianthus/metabolismo , Panthera/fisiología , Alimentación Animal/análisis , Animales , Búfalos , Digestión , Heces/química , Heces/microbiología , Mucosa Intestinal/metabolismo , Intestinos/química , Intestinos/microbiología , Carne , Panthera/sangre , Raíces de Plantas/metabolismo , Prebióticos/normas , Triglicéridos/sangre , Urea/sangre
17.
Rev Biol Trop ; 63(3): 815-25, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26666135

RESUMEN

Little is known about the effects of jaguars on the population of marine turtles nesting in Tortuguero National Park, Costa Rica. This study assessed jaguar predation impact on three species of marine turtles (Chelonia mydas, Dermochelys coriacea and Eretmochelys imbricata) that nest in Tortuguero beach. Jaguar predation data was obtained by using two methodologies, literature review (historical records prior the year 2005) and weekly surveys along the 29 km stretch of beach during the period 2005-2013. Our results indicated that jaguar predation has increased from one marine turtle in 1981 to 198 in 2013. Jaguars consumed annually an average of 120 (SD = 45) and 2 (SD = 3) green turtles and leatherbacks in Tortuguero beach, respectively. Based on our results we concluded that jaguars do not represent a threat to the population of green turtles that nest in Tortuguero beach, and it is not the main cause for population decline for leatherbacks and hawksbills. Future research should focus on continuing to monitor this predator-prey relationship as well as the factors that influence it so the proper management decisions can be taken.


Asunto(s)
Panthera/fisiología , Conducta Predatoria/fisiología , Tortugas/fisiología , Animales , Costa Rica , Monitoreo del Ambiente , Comportamiento de Nidificación , Densidad de Población , Tortugas/clasificación
18.
Conserv Biol ; 28(1): 87-94, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23992599

RESUMEN

The snow leopard (Panthera uncia) inhabits the rugged mountains in 12 countries of Central Asia, including the Tibetan Plateau. Due to poaching, decreased abundance of prey, and habitat degradation, it was listed as endangered by the International Union for Conservation of Nature in 1972. Current conservation strategies, including nature reserves and incentive programs, have limited capacities to protect snow leopards. We investigated the role of Tibetan Buddhist monasteries in snow leopard conservation in the Sanjiangyuan region in China's Qinghai Province on the Tibetan Plateau. From 2009 to 2011, we systematically surveyed snow leopards in the Sanjiangyuan region. We used the MaxEnt model to determine the relation of their presence to environmental variables (e.g., elevation, ruggedness) and to predict snow leopard distribution. Model results showed 89,602 km(2) of snow leopard habitat in the Sanjiangyuan region, of which 7674 km(2) lay within Sanjiangyuan Nature Reserve's core zones. We analyzed the spatial relation between snow leopard habitat and Buddhist monasteries and found that 46% of monasteries were located in snow leopard habitat and 90% were within 5 km of snow leopard habitat. The 336 monasteries in the Sanjiangyuan region could protect more snow leopard habitat (8342 km(2) ) through social norms and active patrols than the nature reserve's core zones. We conducted 144 household interviews to identify local herders' attitudes and behavior toward snow leopards and other wildlife. Most local herders claimed that they did not kill wildlife, and 42% said they did not kill wildlife because it was a sin in Buddhism. Our results indicate monasteries play an important role in snow leopard conservation. Monastery-based snow leopard conservation could be extended to other Tibetan Buddhist regions that in total would encompass about 80% of the global range of snow leopards.


Asunto(s)
Budismo , Conservación de los Recursos Naturales , Panthera/fisiología , Animales , China , Ambiente
19.
Conserv Biol ; 28(2): 580-93, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24372997

RESUMEN

A major question in global environmental policy is whether schemes to reduce carbon pollution through forest management, such as Reducing Emissions from Deforestation and Degradation (REDD+), can also benefit biodiversity conservation in tropical countries. We identified municipalities in Brazil that are priorities for reducing rates of deforestation and thus preserving carbon stocks that are also conservation targets for the endangered jaguar (Panthera onca) and biodiversity in general. Preliminary statistical analysis showed that municipalities with high biodiversity were positively associated with high forest carbon stocks. We used a multicriteria decision analysis to identify municipalities that offered the best opportunities for the conservation of forest carbon stocks and biodiversity conservation under a range of scenarios with different rates of deforestation and carbon values. We further categorized these areas by their representativeness of the entire country (through measures such as percent forest cover) and an indirect measure of cost (number of municipalities). The municipalities that offered optimal co-benefits for forest carbon stocks and conservation were termed REDDspots (n = 159), and their spatial distribution was compared with the distribution of current and proposed REDD projects (n = 135). We defined REDDspots as the municipalities that offer the best opportunities for co-benefits between the conservation of forest carbon stocks, jaguars, and other wildlife. These areas coincided in 25% (n = 40) of municipalities. We identified a further 95 municipalities that may have the greatest potential to develop additional REDD+ projects while also targeting biodiversity conservation. We concluded that REDD+ strategies could be an efficient tool for biodiversity conservation in key locations, especially in Amazonian and Atlantic Forest biomes.


Asunto(s)
Biodiversidad , Carbono/análisis , Conservación de los Recursos Naturales , Panthera/fisiología , Animales , Brasil , Ecosistema , Agricultura Forestal
20.
Rev Biol Trop ; 62(4): 1459-67, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25720180

RESUMEN

Abstract: Attacks by big cats on livestock are one of the major causes of human-felid conflicts and, therefore, an important factor in the conservation of these species. It has been argued that a reduction in natural prey abundance promotes attacks on domestic species, but few studies have tested this statement, and some have delivered contradictory results. We investigated whether the occurrence of attacks to livestock by jaguar and puma relates to the abundance and richness of their natural prey. In the rainy season 2009, we tracked potential prey species counting signs of presence along linear transects in 14 non-attacked cattle farms (control) and in 14 attacked cattle farms in NW Costa Rica. There was a negative relationship between the occurrence of attacks and both species richness (p = 0.0014) and abundance (p = 0.0012) of natural prey. Our results support the establishment of actions to promote support and recovery of natural prey, in order to diminish attacks on livestock, while maintaining jaguar and puma populations.


Asunto(s)
Panthera/fisiología , Conducta Predatoria/fisiología , Puma/fisiología , Animales , Bovinos , Costa Rica , Densidad de Población
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